1

fission

play
noun fis·sion \ˈfi-shən, -zhən\

Definition of fission

  1. 1 :  a splitting or breaking up into parts

  2. 2 :  reproduction by spontaneous division of the body into two or more parts each of which grows into a complete organism

  3. 3 :  the splitting of an atomic nucleus resulting in the release of large amounts of energy

fissional

play \ˈfi-shə-nəl, -zhə-\ adjective

Recent Examples of fission from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fission'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of fission

Latin fission-, fissio, from findere to split — more at bite


2

fission

verb fis·sion

Definition of fission

  1. intransitive verb
  2. :  to undergo fission

  3. transitive verb
  4. :  to cause to undergo fission

First Known Use of fission

1929



FISSION Defined for English Language Learners

fission

play
noun

Definition of fission for English Language Learners

  • physics : a process in which the nucleus of a heavy atom is split apart

  • biology : a kind of reproduction in which a cell or body divides into two or more parts and each part grows into a whole new individual


FISSION Defined for Kids

fission

play
noun fis·sion \ˈfi-shən\

Definition of fission for Students

  1. 1 :  a method of reproduction in which a living cell or body divides into two or more parts each of which grows into a whole new individual

  2. 2 :  the process of splitting an atomic nucleus with the release of large amounts of energy


Medical Dictionary

fission

play play
noun fis·sion \ˈfish-ən also ˈfizh-\

Medical Definition of fission

  1. 1:  a method of reproduction in which a living cell or body divides into two or more parts each of which grows into a whole new individual

  2. 2a:  cleavage 2b:  the splitting of an atomic nucleus resulting in the release of large amounts of energy—called also nuclear fission

fission

verb

fissioned

;

fissioning

\ˈfish-(ə-)niŋ also ˈfizh-\play play

fissional

\ˈfish-ən-əl also ˈfizh-\play play adjective


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